What was found
CLIMBING THROUGH AROUND FL200 NOISE AND VIBRATION FELT FROM NR 1 SIDE, ACCOMPANIED BY HIGH VIBRATION ON NR 1 EICAS INDICATION. HYD 1 LO QTY MESSAGE RECEIVED, FOLLOWED BY HYD1 LOW PRESS EICAS MESSAGE. RAN CHECK LIST AND CONDUCTED FLAPS FULL NORMAL LANDING IN SEA. VIBRATION SUBSIDED ONCE NR 1 ELECTRIC PUMP TURNED ON. VIBRATION LASTED FOR AROUND 1 MINUTE. REMOVED FROM SERVICE. REPLACED NR 1 HYD SYSTEM ENGINE-DRIVEN PUMP AND AC MOTOR PUMP- ALL FUNCTION CHECK NORMAL. AFTER RUNNING NR 1 ENGINE, NO NOISE OR VIBRATION NOTED AND NR 1 HIGH VIBRATION CAS MESSAGE DID NOT DISPLAY. RETURNED TO SERVICE.